CN220040506U - Intelligent cross-connection box - Google Patents

Abstract

The utility model discloses an intelligent cross-connection box, which comprises a box body, a cross-connection assembly, a sensor assembly and a data processing box, wherein the cross-connection assembly and the sensor assembly are arranged in the box body, the data processing box is arranged outside the box body, and the sensor assembly comprises three high-frequency current sensors which are respectively arranged on three cable joints and are used for collecting partial discharge pulse current signals at the joints; the data processing box is internally provided with a partial discharge data collector which is used for converting partial discharge pulse current signals into digital signals; and the signal selector is connected with the three high-frequency current sensors and the partial discharge data collector and is used for selecting one path from the data collected by the three high-frequency current sensors to be transmitted to the partial discharge data collector. The intelligent cross-connection box disclosed by the utility model can realize partial discharge monitoring, and solves the problems of poor detection stability and lower accuracy caused by mutual interference in partial discharge detection of different cables.

Description

Intelligent cross-connection box

Technical Field

The utility model relates to an intelligent cross-connection box, and belongs to the technical field of power equipment.

Background

The metal sheath of the high-voltage transmission cable line generally adopts a segmented cross-connection transposition mode to reduce the induced voltage on the metal sheath, thereby reducing the induced current flowing on the metal sheath. Therefore, the high-voltage cable needs to be segmented, each continuous three-section cable is connected by adopting an intermediate joint to form a cross interconnection section, metal jackets at two sides of the intermediate joint in one cross interconnection section are connected in two cross interconnection boxes through coaxial cables, cross transposition is realized, and the metal jackets at two sides of the cross interconnection section are connected with a ground network through a ground wire.

In the prior art, an intelligent cross-connection box capable of monitoring the induction voltage of the metal outer sheath to the ground in real time so as to ensure the safe operation of a power cable is provided, for example, the Chinese patent application No. 2018202643324, which adopts sensing equipment such as a current transformer, a voltage sensor and the like to continuously monitor the cross-connection box.

However, the cross-connect box described above, while enabling real-time monitoring of the cross-connect box, can only be monitored when significant cable damage occurs. Once abnormality is detected, maintenance is needed immediately, due to the burstiness of the monitoring abnormal result, the work of maintenance personnel is not planned, no matter can be done by the maintenance personnel in part of time, abnormality occurs in a plurality of places in part of time, the problem that the maintenance personnel is insufficient is solved, new potential safety hazard is brought, and the stability of the power system is reduced.

In order to solve the above problems, the inventor proposes a scheme of monitoring partial discharge for different cables in a cross-connection box, and the scheme can detect the cable out of the cross-connection box in time when the cable out of the cross-connection box is slightly abnormal, so that enough arrangement period is provided for maintenance work, but experiments find that three sets of partial discharge monitoring components are needed to be added due to the fact that three paths of cables are arranged in the cross-connection box, and the three sets of partial discharge monitoring components can affect each other, so that stability and accuracy of monitoring results are poor.

For the above reasons, further research into existing intelligent cross-connect boxes is necessary in order to solve the above problems.

Disclosure of Invention

In order to overcome the problems, the present inventors have conducted intensive studies and have proposed an intelligent cross-connect box comprising a box body, a cross-connect assembly disposed in the box body, a sensor assembly including three cable joints, cross copper plates connecting the different cable joints, a sheath protector disposed at the end of the cable joints, and a data processing box disposed outside the box body,

the sensor assembly includes:

three high-frequency current sensors respectively arranged on the three cable joints for collecting partial discharge pulse current signals at the joints,

the three current transformers are respectively arranged on the cable joint and are used for collecting current signals of the high-voltage cable joint;

the data processing box is provided with:

a partial discharge data collector for converting the partial discharge pulse current signal into a digital signal,

the signal selector is connected with the three high-frequency current sensors and the partial discharge data collector and is used for selecting one path from the data collected by the three high-frequency current sensors to be transmitted to the partial discharge data collector;

three loop current collectors which are in communication connection with the current transformer and are used for converting the current signals of the joint positions into digital signals,

the cross-connection box is also provided with a communication component used for transmitting the digital signals output by the partial discharge data collector and the circulation collector to a monitoring center.

In a preferred embodiment, the signal selector comprises two analog switch chips and a singlechip with timing function, and the pin level of the analog switch chips is controlled by the singlechip to realize the selection of three paths of partial discharge pulse current signals.

In a preferred embodiment, in the signal selector, two input pins of the first analog switch chip are respectively connected with the high-frequency current sensor a and the high-frequency current sensor B;

two input pins of the second analog switch chip are respectively connected with the output pin of the first analog switch chip and the high-frequency current sensor C,

the enabling pins of the first analog switch chip and the second analog switch chip are respectively connected with one control pin of the singlechip, so that the singlechip can independently control the enabling of the two analog switch chips.

In a preferred embodiment, the data processing cartridge further has:

the data storage is used for storing the digital signals output by the partial discharge data acquisition unit;

and the comparator is used for comparing the difference value between the existing data of the same cable in the data memory and the new output data of the data acquisition unit, and transmitting the new output data to the communication assembly when the difference value is larger than a preset value.

In a preferred embodiment, the sensor assembly further comprises a voltage transformer, acquiring a voltage signal of the cable junction,

the data processing box is also provided with a voltage collector which is connected with the voltage transformer to calibrate and collect the voltage signals.

In a preferred embodiment, the sensor assembly further comprises a temperature sensor disposed against the outside of the cable for monitoring the temperature of the cable skin.

In a preferred embodiment, the power supply unit of the sensor assembly and the data processing cartridge has a transformer, a photovoltaic assembly and a controller, wherein,

the controller is connected with the photovoltaic module to convert the supplied electric energy sent by the photovoltaic module into stable direct current voltage,

the transformer is connected with municipal power supply and converts alternating current into direct current.

In a preferred embodiment, the communication component is a wireless communication component.

The utility model has the beneficial effects that:

(1) Partial discharge monitoring can be realized, and abnormality can be observed before abnormality occurs, so that the power system is maintained at a better period;

(2) The problems of poor detection stability and lower accuracy caused by mutual interference in partial discharge detection of different cables are solved;

(3) The integrated current transformer and the integrated voltage transformer are monitored, and when abnormality occurs, the abnormality can be rapidly detected, and emergency maintenance is performed.

Drawings

FIG. 1 is a schematic diagram showing the overall structure of an intelligent cross-connect box according to a preferred embodiment of the present utility model;

FIG. 2 shows a schematic diagram of the intelligent cross-header high-frequency current sensor structure according to a preferred embodiment of the present utility model;

FIG. 3 is a schematic diagram showing the construction of a signal selector in an intelligent cross-connect box according to a preferred embodiment of the present utility model;

fig. 4 is a schematic view showing a connection structure between the intelligent cross-connect box sensor assembly and the data processing cartridge according to a preferred embodiment of the present utility model.

Reference numerals illustrate:

1-a box body;

4-a data processing cartridge;

a 5-communication component;

11-cable joint;

12-crossed copper plates;

13-a sheath protector;

21-a high-frequency current sensor;

22-a current transformer;

31-a partial discharge data collector;

a 32-signal selector;

33-loop collector.

Detailed Description

The utility model is further described in detail below by means of the figures and examples. The features and advantages of the present utility model will become more apparent from the description.

The word "exemplary" is used herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are illustrated in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

According to the intelligent cross-connection box provided by the utility model, as shown in figure 1, the intelligent cross-connection box comprises a box body 1, a cross-connection assembly and a sensor assembly which are arranged in the box body, wherein the cross-connection assembly comprises three cable joints 11, cross copper plates 12 connected with different cable joints, a protective layer protector 13 arranged at the end part of the cable joints, and a data processing box 4 arranged outside the box body,

the sensor assembly includes:

three high-frequency current sensors 21, respectively mounted on the three cable joints, for collecting partial discharge pulse current signals at the joints,

three current transformers 22, which are respectively installed on the cable joints and are used for collecting current signals of the positions of the high-voltage cable joints;

the data processing box is provided with:

a partial discharge data collector 31 for converting the partial discharge pulse current signal into a digital signal,

a signal selector 32, connected to the three high-frequency current sensors and the partial discharge data collector, for selecting one path from the data collected by the three high-frequency current sensors to transmit to the partial discharge data collector;

three loop collectors 33, communicatively coupled to the current transformers, for converting the joint position current signals to digital signals,

the cross-connect box also has a communication assembly 5 for transmitting the digital signals output by the partial discharge data collector and the loop current collector to a monitoring center.

Although the traditional cross-connection box can realize real-time monitoring of the grounding cable, the grounding cable can be monitored only when the cable outgoing line is obviously damaged. Once abnormality is detected, maintenance is needed immediately, due to the burstiness of the monitoring abnormal result, the work of maintenance personnel is not planned, no matter can be done by the maintenance personnel in part of time, abnormality occurs in a plurality of places in part of time, the problem that the maintenance personnel is insufficient is solved, new potential safety hazard is brought, and the stability of the power system is reduced.

According to the utility model, on the basis of the traditional cross-connection box, the high-frequency current sensor and the partial discharge data collector are added to monitor the partial discharge performance of the cable, and the cable is monitored to perform early warning before abnormality occurs, so that maintenance staff can maintain the possible abnormal schedule, the utilization rate of the staff is improved, and the hidden danger of the power system is reduced.

Furthermore, as the cross-connection box is internally provided with three cables, three sets of partial discharge monitoring assemblies are required to be added, and the three sets of partial discharge monitoring assemblies can mutually influence to cause the stability and the accuracy of a monitoring result to be poor.

Further, in the utility model, the data processing box is arranged outside the box body of the cross-connection box, so that the interference of other electrified equipment on partial discharge detection can be further reduced.

The high-frequency current sensor and the partial discharge data collector are electronic components commonly used in partial discharge detection, and the specific model is not particularly limited in the utility model.

The current transformer and the loop current collector are electronic components commonly used in mutual inductance current detection, for example, LMZK1 is used as the current transformer, and ACS210D is used as the loop current collector.

Preferably, the signal selector is in communication connection with the partial discharge data collector and the high-frequency current sensor through coaxial cables.

In a preferred embodiment, the high-frequency current sensor 21 is an open-close type clamp sensor, as shown in fig. 2, and the open-close type clamp sensor is adopted, so that the open-close type clamp sensor is convenient to detach and install, and does not need power failure in the installation process, so that the existing cross-connection box is convenient to reform and upgrade.

In a preferred embodiment, the signal selector comprises two analog switch chips and a singlechip with timing function, and the pin level of the analog switch chips is controlled by the singlechip to realize the selection of three paths of partial discharge pulse current signals.

The stability of the signal collected in the partial discharge detection is poor, and the conventional signal selector is easy to cause signal distortion, so that the detection stability is reduced.

In the utility model, the analog switch chip is adopted, has the characteristics of low on-resistance and low delay, and can reduce the voltage drop of the signal in the transmission process, thereby reducing the distortion rate of the signal and improving the detection stability.

In the present utility model, the specific model of the analog switch chip is not particularly limited, and a person skilled in the art can freely select the analog switch chip according to actual needs, for example, BL1551 SC70-6 is adopted.

As shown in fig. 3, two input pins (pins A1 and A2) of the first analog switch chip are respectively connected with a high-frequency current sensor a and a high-frequency current sensor B;

two input pins of the second analog switch chip are respectively connected with an output pin (B pin) of the first analog switch chip and the high-frequency current sensor C,

the enabling pins (ENB pins) of the first analog switch chip and the second analog switch chip are respectively connected with one control pin of the singlechip, so that the singlechip can independently control the enabling of the two analog switch chips.

In a preferred embodiment, as shown in fig. 4, the data processing cartridge further has:

the data storage is used for storing the digital signals output by the partial discharge data acquisition unit;

and the comparator is used for comparing the difference value between the existing data of the same cable in the data memory and the new output data of the data acquisition unit, and transmitting the new output data to the communication assembly when the difference value is larger than a preset value.

In the present utility model, the specific model of the data memory and the comparator are not particularly limited, and a person skilled in the art can select according to actual needs, for example, the data memory adopts a flash memory chip, and the comparator adopts a singlechip.

The detection of the high-frequency current sensor is real-time, that is, the detection of partial discharge is real-time, however, in practical use, frequent detection has little meaning, and a large amount of signal transmission resources are wasted, especially when wireless signal transmission, such as 4G/5G communication, is adopted, and the cost is increased obviously. However, the periodic detection is adopted, partial discharge is possibly generated, but the phenomenon cannot be found by the monitoring center due to the fact that the periodic detection time is not reached.

Optionally, the monitoring center can actively call the output data of the partial discharge data collector at any time.

In a preferred embodiment, the sensor assembly further comprises a voltage transformer, acquiring a voltage signal of the cable junction,

the data processing box is also provided with a voltage collector which is connected with the voltage transformer to calibrate and collect the voltage signals.

Through voltage transformer and voltage collector, measure and in time transmit monitoring center to the voltage, can in time discover the unusual that the cable appears to quick processing. Preferably, the voltage transformer adopts a 0-100A single-mode accurate voltage transformer (for example, JDZX9-35 voltage transformer), and the voltage collector adopts an accurate voltage collector (for example, an MCE-AV42 voltage intelligent collector) so as to accurately detect the voltage.

In a preferred embodiment, the sensor assembly further comprises a temperature sensor, the sensor is arranged to be closely attached to the outer side of the cable and used for monitoring the skin temperature of the cable, and the phenomenon that the cable is too high in temperature due to the fact that the cable sheath is damaged is timely found, so that the occurrence rate of potential safety hazards of the circuit is reduced.

According to a preferred embodiment of the utility model, the power supply unit of the sensor assembly and the data processing cartridge has a transformer, a photovoltaic assembly and a controller, wherein,

the controller is connected with the photovoltaic module, converts the supplied electric energy sent by the photovoltaic module into stable direct-current voltage, supplies power to the sensor module and the data processing box,

the transformer is connected with municipal power supply, converts alternating current into direct current, and supplies power to the sensor assembly and the data processing box.

Preferably, the photovoltaic module is arranged above the box body, so that flushing of rainwater and the like to the box body is reduced, and the service life of the box body is prolonged.

Preferably, the power supply unit is arranged on the outer side of the box body, so that interference to detection of the sensor is avoided.

According to the utility model, the communication component adopts a wireless communication component, more preferably adopts a 4G/5G module for communication, and reduces wiring cost and installation cost.

In a preferred embodiment, the communication assembly is provided in the data processing cartridge, avoiding interference with the monitoring of the partial discharge.

In the description of the present utility model, it should be noted that the positional or positional relationship indicated by the terms such as "upper", "lower", "inner", "outer", "front", "rear", etc. are based on the positional or positional relationship in the operation state of the present utility model, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," "fourth," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The utility model has been described above in connection with preferred embodiments, which are, however, exemplary only and for illustrative purposes. On this basis, the utility model can be subjected to various substitutions and improvements, and all fall within the protection scope of the utility model.

Claims (8)

1. An intelligent cross interconnection box comprises a box body, a cross interconnection assembly and a sensor assembly, wherein the cross interconnection assembly and the sensor assembly are arranged in the box body, the cross interconnection assembly comprises three cable joints, cross copper plates connected with different cable joints, and a protective layer protector arranged at the end part of the cable joints, and is characterized by further comprising a data processing box arranged outside the box body,

the sensor assembly includes:

three high-frequency current sensors respectively arranged on the three cable joints for collecting partial discharge pulse current signals at the joints,

the three current transformers are respectively arranged on the cable joint and are used for collecting current signals of the high-voltage cable joint;

the data processing box is provided with:

a partial discharge data collector for converting the partial discharge pulse current signal into a digital signal,

the signal selector is connected with the three high-frequency current sensors and the partial discharge data collector and is used for selecting one path from the data collected by the three high-frequency current sensors to be transmitted to the partial discharge data collector;

three loop current collectors which are in communication connection with the current transformer and are used for converting the current signals of the joint positions into digital signals,

the cross-connection box is also provided with a communication component used for transmitting the digital signals output by the partial discharge data collector and the circulation collector to a monitoring center.

2. An intelligent cross-connect box as in claim 1 wherein,

the signal selector comprises two analog switch chips and a singlechip with a timing function, and the pin level of the analog switch chips is controlled by the singlechip to realize the selection of three paths of partial discharge pulse current signals.

3. An intelligent cross-connect box as in claim 2 wherein,

in the signal selector, two input pins of a first analog switch chip are respectively connected with a high-frequency current sensor A and a high-frequency current sensor B;

two input pins of the second analog switch chip are respectively connected with the output pin of the first analog switch chip and the high-frequency current sensor C,

the enabling pins of the first analog switch chip and the second analog switch chip are respectively connected with one control pin of the singlechip, so that the singlechip can independently control the enabling of the two analog switch chips.

4. An intelligent cross-connect box as in claim 1 wherein,

the data processing cartridge further has:

the data storage is used for storing the digital signals output by the partial discharge data acquisition unit;

and the comparator is used for comparing the difference value between the existing data of the same cable in the data memory and the new output data of the data acquisition unit, and transmitting the new output data to the communication assembly when the difference value is larger than a preset value.

5. An intelligent cross-connect box as in claim 1 wherein,

the sensor assembly further comprises a voltage transformer for acquiring a voltage signal of the cable joint,

the data processing box is also provided with a voltage collector which is connected with the voltage transformer to calibrate and collect the voltage signals.

6. An intelligent cross-connect box as in claim 1 wherein,

the sensor assembly further comprises a temperature sensor which is arranged to be clung to the outer side of the cable and used for monitoring the surface temperature of the cable.

7. An intelligent cross-connect box as in claim 1 wherein,

the power supply unit of the sensor assembly and the data processing box is provided with a transformer, a photovoltaic assembly and a controller, wherein,

the controller is connected with the photovoltaic module to convert the supplied electric energy sent by the photovoltaic module into stable direct current voltage,

the transformer is connected with municipal power supply and converts alternating current into direct current.

8. An intelligent cross-connect box as in claim 1 wherein,

the communication assembly adopts a wireless communication assembly.